The present invention relates to selection of a preferred network for roaming and, more particularly, but not exclusively to a method or system for influencing a roaming mobile unit to make such a selection.
Mobile telephones are becoming more and more a part of life, and people expect their mobile telephones to work everywhere, including when they cross International borders. That is to say people do not expect to have to reprogram or replace their telephones every time they travel abroad. As a result, a secondary mobile telephone infrastructure has developed, known as the roaming infrastructure, to provide support for mobile telephones that log in for cellular connections in countries which are not their own.
Any given region or country has a number of cellular networks providing signals. A user subscribes to one of these networks and whenever he switches on his telephone it logs into the network to which he has subscribed, otherwise referred to as his home network. The mobile telephone simply ignores other, competing networks. When mobile devices are outside of their home region, there is also likely to be a range of competing networks. However this time there is no default choice for logging on since none of these networks are the user's home network. Nevertheless there may be good reason for selecting one network over another. One network might simply offer a better tariff than the others, or may offer greater reliability, or the home network may want to concentrate all of its roamers in a single network in order to obtain a volume discount, or a particular network in the foreign country may simply belong to the same group as the user's home network.
Generally mobile telephones have preprogrammed settings, which are often stored in an on-board programmable unit. In GSM telephones such settings may be stored in the subscriber identification module or SIM card. It is possible to preprogram the unit to carry a preference order for selecting networks in the given region. Thus a mobile telephone whose home network is in France may have been provided with a preference list giving the order for selection of networks in the UK. When in the UK, the mobile telephone attempts first of all to log in to the network at the top of the list, then the second and so on until it succeeds.
There are two major disadvantages with the preprogrammed list. First of all the capacity available on board the SIM is limited. Thus it is possible to provide preference data for a small number of most likely regions only. In most regions of the world the mobile phone simply has no guidance. Secondly, a given provider's list of which networks are preferred in a given country is not necessarily static. New deals can be signed, companies can merge and new tariffs worked out so that the economics of the situation changes at short notice. However there is no efficient way to remotely update the telephone. It is possible to remotely update a SIM card with a new data file, but the update would have to be sent to every single subscriber including many who have no intention of ever roaming in the given region, and this is simply wasteful of resources, and especially of SIM card memory.
Considered in greater detail, as the mobile telecom market becomes more and more competitive, mobile network operators join larger business groups either as subsidiaries or as members of an alliance organization.
Striving to maximize group or alliance revenue as well as recognizing the roaming segment as an increasingly significant revenue generator, group members want their outbound roamers to register with other group member networks in the countries they visit. These networks are designated by operators as their Preferred Networks.
Yet non-group network operators may also have reasons to designate some networks as preferred networks in countries where their subscribers roam. Among these reasons are different roaming agreements, potential coverage and traffic volume. New roaming agreements, new tariff schemes and changing preferences are established facts. In addition, preferences can be based on the kind of user, so-called community-based preferences. Thus for example prepaid users may have different preferences than GPRS users. The 3G arena may in fact present different preferences per service, thus for example the preferred roaming network for voice services may be different than the one for data services. For example the best network for voice may be selected based on the tariff offered, whereas the best network for data services may be selected on the basis of technical reliability and bandwidth.
For these reasons network operators would like to have the ability to direct the handsets of their outbound roamers to preferred networks whenever they roam in foreign countries. Such directing tools must be flexible enough to allow network redirection at any time independently of the operational state of the handset, as long as the handset is powered and the preferred network provides the required air-link coverage.
Furthermore, the ability to seamlessly and flexibly steer handsets to the preferred network can be used by operators as a means to achieve better terms and conditions of the roaming agreements they sign with partnering network operators.
Existing SIM and over the air (OTA) solutions for updating a SIM card cover handsets complying with the GSM Phase 2+ standard. Earlier handset versions support downgraded functionality. Nevertheless, as explained, most installed SIM cards have a small memory that is not sufficient for any significant OTA download and for running any required preferred network applets. In addition, limited processing capability means that handsets are only able to scan the first few networks in any list of preferred networks that they may be carrying.
Furthermore, there are networks that do not use SIM cards at all, such as CDMA-based networks, but still want to control roaming distribution. In addition, the install base of existing SIM cards includes devices of various generations with different capabilities, so the problem is not only the lack of functionality of the SIM as such, but the lack of a generic solution, which can cover 100% percent of the devices on a given network, is applicable to all networks and is effective and provides the desired features in an effective manner.
As a result of the above, network operators seek a home-network-based, handset independent remote control of the network selection process that is carried out by the roaming handset. That is to say, the solution is to be independent of the SIM and handset themselves.
It is anticipated that operators may also want a complementary home-network control on handset operation of the network selection process. Finally, operators wish to have the flexibility to apply different activation policies for the preferred network function based on different parameters such as the visited country/network, different times and different subscriber segments.
There is thus a widely recognized need for, and it would be highly advantageous to have, a roaming network selection preference system devoid of the above limitations.